This application is for renewal of the Nathan Shock Center of Excellence in Basic Biology of Aging at the University of Washington. This Center has over the past 4 years provided resources in support of the large community of investigators that study the basic biology of aging in this region. We serve a broad spectrum of externally funded, peer-reviewed research programs, ranging from Centers to individual investigator grants. Proposed components of our renewal include a Resources Core with 3 components: 1.) Transgenic Animal Model Development Resource Core; 2) Cytometry Resource Core; 3) Gene Expression Resource Core. In this next funding period, the Transgenic Animal Model Development Resource Core will work to develop and apply constructs for developmental and exogenous regulation of transgenes. We will continue our philosophy of helping a large number of investigators to develop mouse models for aging studies. The Cytometry Core will in the future provide confocal microscopy services in addition to flow cytometry and cell sorting. The Gene Expression Core is an outgrowth of our former small core for protein-protein interactions; we propose to expand this core to provide expert assistance in the analysis of gene expression using cDNA arrays on glass and nylon membranes. The Research Development Core will continue to support junior faculty and pilot study projects in the basic biology of aging. The Program Enrichment Core supports administrative management, an external advisory panel, and a program of courses and seminars.